package com.can.add;

import java.util.concurrent.CountDownLatch;

//计数器
public class CountDownLatchDemo {
    public static void main(String[] args) throws InterruptedException {
        //倒计时，总数是6, 必须要执行任务的时候，在使用
        CountDownLatch countDownLatch = new CountDownLatch(6);
        for (int i = 1; i <= 6; i++) {
            new Thread(()->{
                System.out.println(Thread.currentThread().getName()+" Go out");
                countDownLatch.countDown(); //数量-1
            },String.valueOf(i)).start();
        }

        countDownLatch.await(); //等待计数器归零，然哈再向下执行

        System.out.println("Close Door");
    }
}
